(gnus-agent-union): new function.

(gnus-agent-fetch-headers): Use it.

diff --git a/lisp/gnus-agent.el b/lisp/gnus-agent.el
index 27442fa..3a4d4bb 100644 (file)
--- a/lisp/gnus-agent.el
+++ b/lisp/gnus-agent.el
@@ -867,13 +867,29 @@ the actual number of articles toggled is returned."
        (insert "\n"))
       (pop gnus-agent-group-alist))))
 
+(if (fboundp 'union)
+    (defalias 'gnus-agent-union 'union)
+  (defun gnus-agent-union (l1 l2)
+    "Set union of lists L1 and L2."
+    (cond ((null l1) l2)
+         ((null l2) l1)
+         ((equal l1 l2) l1)
+         (t
+          (or (>= (length l1) (length l2))
+              (setq l1 (prog1 l2 (setq l2 l1))))
+          (while l2
+            (or (memq (car l2) l1)
+                (push (car l2) l1))
+            (pop l2))
+          l1))))
+
 (defun gnus-agent-fetch-headers (group &optional force)
   (let ((articles (gnus-list-of-unread-articles group))
        (gnus-decode-encoded-word-function 'identity)
        (file (gnus-agent-article-name ".overview" group)))
     ;; Add article with marks to list of article headers we want to fetch.
     (dolist (arts (gnus-info-marks (gnus-get-info group)))
-      (setq articles (union (gnus-uncompress-sequence (cdr arts))
+      (setq articles (gnus-agent-union (gnus-uncompress-sequence (cdr arts))
                            articles)))
     (setq articles (sort articles '<))
     ;; Remove known articles.